The bodies of 78 young men, all executed with a single gunshot, were found Tuesday in a river in Aleppo city, adding to the grim list of massacres committed during Syria's 22-month conflict.

The gruesome discovery came ahead of a briefing by peace envoy Lakhdar Brahimi to the U.N. Security Council on the uprising, which the United Nations says has left more than 60,000 people dead.

Abu Seif, a rebel fighter, said 78 bodies were retrieved from the Quweiq River and that 30 more were still in the waters but out of reach because of regime snipers.

"The regime threw them into the river so that they would arrive in an area under our control, so the people would think we killed them," he said.

But a security official accused "terrorists," the regime term for the rebels, of the killings, adding the victims were residents kidnapped from the opposition-held district of Bustan al-Qasr.

Their families had tried to negotiate their release before they were killed overnight, he said.

There was no immediate claim of responsibility, but the official SANA news agency said the jihadist Al-Nusra Front carried out the executions.

"Terrorist groups from al-Nusra Front in Aleppo carried out a mass execution of dozens of abducted people and threw their bodies in the Quweiq River," the agency said.

Al-Nusra, which first gained notoriety for its suicide bombings in Syria, has evolved into a formidable fighting force leading attacks on battlefronts throughout the embattled country.

Its extremist tactics and suspected affiliation to the al-Qaida offshoot in Iraq have landed it on the U.S. list of terrorist organizations.

The Syrian Observatory for Human Rights gave a toll of 65 bodies but warned the figure could rise significantly.

"They are in their 20s and were executed by a bullet to the head. Most of them had their hands tied behind their backs and were in civilian clothes," said the watchdog.

The scene on the banks of the Quweiq was grim, as muddied corpses are dredged out and hundreds of distressed people flocked around to see if they could spot among the bodies a father, a brother, a son or a husband.

"My brother disappeared weeks ago when he was crossing (through) the regime-held zone, and we don't know where he is or what has become of him," said Mohammed Abdel Aziz.

Volunteers helped place the bodies on a truck. They were then taken to a school where they were laid out and covered.

"We do not know who they are -- they were not carrying papers," a volunteer said as an Agence France Presse correspondent counted at least 15 bodies on one truck.

A number was placed next to each body and their faces were left uncovered to allow the identification by relatives at the school, where the nauseating stench of death lingered.

"There are those who drowned because the were shot in the legs or abdomen before being thrown into the water," said a nurse, noting some may have been killed up to three days ago.

Violence raged elsewhere in Aleppo province, where seven children were killed in air strikes on the town of Safireh, the Observatory said, giving a toll of 91 people killed across Syria on Tuesday.

And in Damascus a member of parliament was seriously injured when a explosive device strapped to his car exploded, the Observatory said.

The bloodshed came as rebels captured a vital bridge across the Euphrates River in Deir Ezzor city, largely severing an army supply route to Hasakeh province further north.

The nearby regime security headquarters and a smaller bridge were also captured, prompting retaliatory air strikes on the critical crossings.

"These gains in Deir Ezzor are very important because this strategic city is the gateway to a region rich in oil and gas resources," said Observatory director Rami Abdel Rahman.

"If the rebels continue to progress and gain control of what is left of military-held positions... it will be the first major city to fall into the hands of the rebels," said Abdel Rahman.

On the eve of a donors' conference in Kuwait, charity organizations pledged $182 million (136 million euros) for Syrians displaced at home or who have fled abroad.

U.S. President Barack Obama announced an extra $155 million dollars to aid refugees fleeing what he said was "barbarism" propagated by the government of President Bashar Assad.

"bigbozo cant you for once post sthg that has meaning?"....that's all you got their schizo? Smack your empty skull you Farsi! Branding is totally justified when a pathetic non-Lebanese posts trash supporting terrorists/scums/cold-blooded killers. You and your kind is why this world will never see peace and tranquility. YOU & your leaders preach hate/anger/repression/terror. If you like it so much....keep your trash in Iran and don't bring/force it on Lebanese! Mustool!

Let us find out who were these persons...were they government supporters or Rebel supporters? ALL the bodies need to be identified and for the rebels to put many in mass graves makes it look like a cover up.

Both sides have committed war crimes. We have seen Al-qaeda linked groups in Iraq, Pakistan, and elsewhere who kill people not just for their politics, but because they are not Sunnis. If you really care about the Syrian people you would denounce ALL the killings and try hard to find out who is doing these killings. Going by this article alone, it is very hard to tell who did this.

Mowaten, I think the rebels were trying to imply that the bodies somehow floated down the river to their area without any body seeing them. It is sick how both sides lie and ALWAYS claim the other for massacres without taking any responsibility.

poor FT just answering to look smarter... if you had an ounce of intelligence you d noticed that mowaten what asking about why couldn t it be the rebels and i was returning the question why couldn t it be the syria narmy: same logic...

but of course in your stupidity you didn t notice that.
seems you know better than anyone and you already know who killed them! proof of your idiocy and twisted baathist mind.

the rebels themselves have massacered people in syria before espically alawites..and does anyone ever report that no..simply becasue the FSA who supports al nusra cannot be seen that way to the world..it is a planned media in favor of them..why dont you repprt everything and let the people decide becasue in my opinion the simple fact that the oppoesiton is refusing to hold talks for a peacful transiton indicates one thing and that is that they are simply looking for blood..what do they think that if bashaa is gone they will automaticly becaome a democracy..and what exactly will they do with all those guns they habded out to people..and what about al nusra who becasue of the FSA has gained massaive support..so why dont they jst give talks a chance instead of simply discarding them ..if they say they want to be a democracy then open the door to tlaks first